Abstract:

To analyze the epidemiological characteristics of thyroid nodules and to evaluate the value of the present methods for diagnosing thyroid nodules. MethodA retrospective study of 1?474 patients who had undergone surgery for thyroid nodules was made.  Results① There were 286 males and 1?188 females. 1?141(77.40%) patients were diagnosed with benign nodules and 333(22.60%) malignant nodules. The malignant rate was higher in males than in females（28.3% vs 21.3%, P<0.05）. ② The prevalence of thyroid cancer did not differ between patients with a solitary nodule and patients with multiple nodules (33.1% vs 27.6%, P=0.287). Those individual sonographic characteristics that showed a statistically significant difference in the malignant group were: ill defined margin, solid component, hypoechoic nodule, microcalcifications, internal blood flow and enlarged cervical lymph node(P<0.001). There were no differences between the benign and malignant groups for absent of halo and coarse calcifications (P>0.05). ③ The accuracy, sensitivity, and disaccording rate of frozen section examinations was 96.0%,  91.9%,  0.5%, respectively.  Microcarcinoma was found in 68 patients by paraffin section examination, of which 26(38.8%) had lymph node metastases. ConclusionThyroid nodules were found more often in women than in men,  but the malignancy rate was higher in men than in women. Ultrasonographic features could be helpful in differentiating benign and malignant nodules. Frozen section examination is of value in diagnosing thyroid nodules and plays a key role in determination of the extent of thyroidectomy. 

Key words: Thytoid nodule;  Diagnosis;  Ultrasonography;  Frozen section examiantion